Global EV transition hinges on policy adoption, cost reductions

A new study finds that the global shift to electric vehicles (EVs) could significantly reduce energy use and carbon emissions, but only if governments act aggressively to lower costs and align policies across regions.

Publishedin the March edition of the journal Resources, Environment and Sustainability, the paper, "Future Changes in CO2 Emissions in the Shift to Electric Mobility in Countries With Varied Levels of Zero-Emission Vehicle Policies," examines how the pace and scale of EV adoption vary widely worldwide, shaped by policy strength, economic conditions and infrastructure readiness within each country.

The researchers used the widely accepted Global Change Analysis Model developed by the Pacific Northwest National Laboratory's Joint Global Change Research Institute to evaluate how different policy scenarios influence vehicle electrification and its downstream impacts on energy systems and emissions.

The team found that a uniform 20% reduction in non-energy costs, including factors such as vehicle purchase price, maintenance and insurance, could dramatically accelerate EV adoption. Under such a scenario, EV market share could rise from roughly 25 to 50% to as high as 70 to 85% globally after 2035, depending on assumptions about technology, energy prices and regional trends.

First author Shuai Pan, former postdoctoral researcher at Cornell who is now at China's Nanjing University of Information Science and Technology, said that such a marked shift in EV adoption rates would substantially cut energy consumption and tailpipe carbon dioxide emissions in major markets including the United States, Europe and China, while slowing emissions growth in developing regions such as India, Southeast Asia and West Africa.

"Cost remains the most powerful lever," Pan said.

The authors conclude that policy-driven reductions in non-energy costs achieved through subsidies, manufacturing scale and technological innovation are essential to making EVs competitive with conventional internal combustion engine vehicles.

The study also highlights stark regional disparities. Wealthier economies with established infrastructure and strong policy support are currently leading the transition, while many developing countries face barriers including limited charging networks, lower consumer purchasing power and weaker policy frameworks.

Even with rapid EV adoption, the researchers emphasize that electrification alone is not a climate solution.

"While EVs reduce emissions from transportation, they can shift emissions to other sectors - particularly electricity generation and hydrogen production - if those systems remain reliant on fossil fuels," said co-author H. Oliver Gao, the Howard Simpson 1942 Professor in the School of Civil and Environmental Engineering and director of the Center for Transportation, Environment, and Community Health at the Cornell Duffield College of Engineering.

The modeling shows that battery electric vehicles would increase electricity demand, but only modestly, accounting for about 13.5% of total electricity consumption in the U.S. under a high-adoption scenario. However, without cleaner power generation, emissions from the electricity sector could offset a significant share of the gains from electrification.

Similarly, expanded use of hydrogen-powered vehicles would increase demand for hydrogen production, which today is largely fossil fuel-based.

"Scaling up low-carbon, green hydrogen will be critical to realizing the full emissions benefits of fuel cell vehicles," Gao said.

The study underscores the importance of coordinated, cross-sector policy. Scenarios that paired EV adoption with clean energy standards produced far greater net emissions reductions than electrification alone.

Stronger international collaboration is also necessary, the researchers said. Support from leading automotive markets, such as financial investment and technology transfer, will be essential to ensure that developing countries can participate in, and benefit from, the global transition.

Without such cooperation, the authors warn, the EV transition risks deepening global inequalities, with emissions reductions concentrated in wealthier regions while infrastructure and cost barriers persist elsewhere.

"EVs can be a powerful tool for climate mitigation, but their success depends on timing, ambitious policy adoption, and the parallel decarbonization of the broader energy system," Pan said.

Chris Dawson is a communications coordinator for Duffield Engineering.